Tundish cleaning and preheating apparatus



Jan. 27, 1970 P. Z.-ANDERSON 3,491,938

' v TUNDISH CLEANING AND..PREHEATING APPARATUS Filed Feb. 5. 1968 l 4 Sheets-Sheet 1 INVENTOR. PAUL Z. ANDERSON N ATTORNEYS P. Z. ANDERSON TUNDISH CLEANING AND- PREHEATING APPARATUS Jan. 27, 1970 4 Sheets-Sheet 2 Filed Feb. 5. 1958 F iG 6 INVENTOR,

PAUL z. ANDERSON m M w ATTORNEYS Jan. 27, 1970 Filed Feb. 5, 1968 P. Z. ANDERSON TUNDISH CLEANING AND PREHEATING APPARATUS 4 Sheets-Sheet 3 FIG...3

INVENTOR. PAUL Z. ANDERSON ATTORNEYS TUNDIS H CLEANING AND PREHEATING APPARATUS Filed Feb. 5. 1968 4 Sheets-Sheet 4 PAUL Z. ANDERSON WPWWWJ ATTORNEYS United States Patent O 3,491,988 TUNDISH CLEANING AND PREHEATING APPARATUS Paul Z. Anderson, Whittier, Calif., assignor to American Pipe and Construction Co., Monterey Park, Calif., a

corporation of California Filed Feb. 5, 1968, Ser. No. 703,096 Int. Cl. F23m 9/00; F27d 21/00, 23/02 US. Cl. 2632 24 Claims ABSTRACT OF THE DISCLOSURE Apparatus is provided in connection with a turret-type tundish carrier on continuous casting installations for cleaning and preheating the tundishes without removing them from the turret. The apparatus specifically includes apparatus for turning the tundish on its side so that its face is vertical, and a combined heat shield for oxygen lancing operations and preheating unit which can be applied against the vertical face of the tipped tundish. Flame diverters are provided to protect the tipping mechanism from the preheating unit.

Background of the invention The invention pertains to a tundish preheating and cleaning system by which a tundish can be cleaned and preheated while it is on the turret of a turret-type continuous casting machine, so that it can be moved into casting position without handling and with a minimum loss of heat.

US. Patent No. 3,344,847 to Beemer describes such a turret-type continuous casting apparatus. In that patent, tundishes and ladles are mounted on a turret on which they can be arcuately moved through various positions. As far as the tundishes are concerned, one of these positions is the casting position in which they receive molten metal from a ladle and distribute the metal into one or more molds. Another position is the cleaning and preheating position into which each tundish is moved after the termination of a cast to be cleaned out and preheated while another tundish may simultaneously be used in the casting position for the next cast.

Inasmuch as continuous casting apparatus of the type described relies for its effectiveness on split-second timing and a minimum of handling, it was found to be undesirable to remove the tundishes from the turret for the cleaning and preheating operation and then rehang them on the turret when they were ready to be moved into casting position. It therefore became necessary to provide a compact and effective arrangement whereby tundishes could be cleaned and preheated right on the turret in a minimum of time and with a minimum of effort. The present invention fills this need.

SUMMARY OF THE INVENTION The apparatus has four distinct parts. The first is a mechanism, preferably mounted on the tundish car or carrier, for mechanically tilting the tundish on its side so that its face is vertical for cleaning and preheating. The second is a heat shield which can be swung into and out of position opposite the vertical face of the tundish, and which protects an operator during the processs of oxygen lancing the tundish to clean it out. The third is a preheating head which can be swung into position opposite the vertical face of the tipped tundish and can be brought into close contact therewith for effective preheating of the tundish while it is on the turret in its tipped position. The fourth part, where it is required by the nature of the mechanism, includes flame suppressor means of the air curtain type which divert the flames of the preheating unit away from the tundish car and associated mechanism to prevent that mechanism from becoming overheated and failing.

A useful feature of the invention is the combination of the heat shield for the oxygen lancing operation and of the preheating apparatus into a single piece of equipment in such a manner that the heat shield serves as the spacing member which brings the preheating head into close contact with the tundish when the preheating head is in operating position while keeping the heat shield spaced a considerabble distance from the tundish when the heat shield is in operating position.

Inasmuch as the nature of the apparatus prevents the maintaining of close tolerances, and particularly since the heat involved in the casting processes occasions considerable warpage of the tundishes and other components of the system, universal mounting means are provided on the preheating head so that it can be brought into the closest possible contact with the tundish regardless of the precise position of the tundish and regardless of even major warpage of any material component.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an over-all plan view of the apparatus of this invention;

FIG. 2 is a fragmentary elevation along line 2-2 of FIG. 1 showing the tundish tilting mechanism;

FIG. 3 is a fragmentary elevation illustrating one use of the apparatus of FIG. 1;

FIG. 4 is an elevation generally along line 44 of FIG. 1;

FIG. 5 is an elevation generally along line 55 of FIG. 1; and

FIG. 6 is a detail plan view of the tundish and preheater arrangement illustrating the manner in which the preheating head is moved against the tundish.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring first to FIG. 1, the turret of the turret-type casting apparatus of Patent No. 3,344,847 is generally indicated at 10. A tundish car 12 is suspended for arcuate movement on the turret 10 in a manner generally indicated in Patent No. 3,344,847. The tundish car 12 extends radially outward from the turret 10 and has a pair of side arms 14, 16 comprising bearings 18, 20 in which a tundish 22 is tiltably suspended by hinge pins 24, 26. The bearings 18, 20 are formed in bearing plates 21, 23 whose position can be adjusted for alignment purposes by adjustment screws 40, 64 which cause-the bearing plates 21, 23 to slide along the side arms 14, 16.

An air cylinder 28 is mounted on the tundish car 12 on a pivot 29 to operate the tilt mechanism for the tundish in a manner shown in more detail in FIG. 2.

As will be best seen in FIG. 2, the tundish 22 is provided with a cradle 30 which is supported on a shaft 27 coaxial with the pins 24, 26, but mounted in spaced relation thereto on a bracket 31 supported on side arm 16. Fixed with respect to the cradle 30 is a lever arm 32 which is pivotally connected to the piston rod 34 of air cylinder 28. Consequently, the tundish 22, which is in the phantom line position of FIG. 2 during use, can be tilted to the full line position of FIG. 2 by operating the air cylinder 28 so as to extend the piston rod 34.

In operation, a tundish car 12, at the end of a cast, is brought around the turret 10 to the cleaning and preheating station with which the present invention is concerned. When the car reaches the cleaning and preheating station, an air supply (not shown) is connected to the cylinder 28, and the cylinder 28 is operated to tilt the tundish 22 onto its side as shown in the full line position in the drawings.

As will be evident from an inspection of FIG. 3, the Slag in the tundish 22 will thereupon pour out through the open face 36 of the tundish 22 into the slag box 38 (for reasons of clarity, FIG. 3 does not show the tilting mechanism of the tundish, but only the bearing plate adjusting mechanism 40). The slag box 38 is so positioned that the shield-and-preheater assembly 56 can be swung around the kingpost 58 without removing the slag box, the preheater and tundish coming together above it. When desired, the slag box can be lifted away by a crane (not shown) whenever there is no tundish car at the cleaning station and the shield-and-preheater assembly 56 is in the full-line position of FIG. 1.

When all the slag has run out into the slag box 38-, the operator 42 steps behind the heat shield 44 (best shown in FIG. 4; note that the hot refractory face 94 of the preheating head of necessity always faces away from the operator in this arrangement) and pushes the oxygen lance 46 through the slot 48 in the heat shield 44 into the tundish 22. The operator then maneuvers the oxygen lance 46 around in the tundish 22 until all remaining slag that has stuck to the refractory walls of the tundish 22 is burned off in a manner well known in the art. The slot 48, it will be understood, is as narrow as possible while still giving the operator a suflicient view of the tundish 22 to enable him to properly manipulate the oxygen lance 46.

Referring again to FIG. 4, the locking bar 50 has, during the previously described process, been locked into engagement with the fitting 53 attached to the floor to prevent any accidental movement of the heat shield 44. When the oxygen lancing operation is finished, the locking bar 50 is raised by means of handle 52 into the position shown in FIG. 4 and is kept in the disengaged position by engagement of handle 52 with the guide 54. The entire shield and preheater assembly 56 can now be swung about kingpost 58 into the dotted line position of FIG. 1.

Before swinging the assembly 56 around, however, it is necessary to pivot the preheating head 60 about the hinge 62 to a sufficient degree so that its upper right-hand corner (in FIG. 1) will clear the upper (in FIG. 1) adjustment mechanism 64. The corresponding position of the preheating head 60 is shown in phantom lines in FIG. 6.

The pivoting of preheating head 60 about pivot 62 is accomplished by releasing the resilient latch 66 (FIGS. 4 and 6) by moving its outer end upwardly and pulling in a clockwise direction (in FIG. 6) on the pivot bar 68. This will cause the hinge bracket 70 to pivot about pin 72 and eventually swing the preheating head 60 about pivot 62 by pulling on link arm 74 which is hinged to the hinge bracket at 76 and to the preheating head 60 at 78.

When the shield-and-preheater assembly 56 has been swung about the kingpost 58 to the point where the preheating head 60 is in the position shown in dotted lines in FIG. 6, the pivot bar 68 is swung counterclockwise back to the position shown in FIG. 6 and latched by means of the latch 66. This pivots the preheating head 60 counterclockwise about pivot 62, presses it against the tundish 22, and locks it in place by moving the link 74 over center with respect to the pivot point 72.

Referring now further to FIG. 4, it will be noted that the burner assembly 80 is pivotally suspended on a horizontal axis 82 from supporting arms 84 which are themselves pivoted to the frame of the preheating head 60 at 86. Air cylinders 88, 90 (FIGS. 1, 4, and 6) are connected between the frame of the preheating head 60 and the burner assembly 80. It will be understood that by operating the air cylinders 88, 90 to push the burner assembly 80 as far towards the tundish 22 in FIG. 6 as it will go, the front face 92 of the burner assembly 80 will come to lie against the open face 36 of the tundish 22 as closely as possible regardless of any Warpage of the tundish 22.

With the preheating head thus in place, preheating of the tundish 22 can begin. For this purpose, a gas-air fuel mixture is brought through a standpipe 94 in kingpost 58 and through a flexible hose 96 to the rigid distribution pipes 98, 100. From there the mixture is distributed to the burners 102, 104 and is ignited at the refractory face 92 of the burner assembly 80.

Inasmuch as the gas is supplied to the burners under considerable pressure, the flames would normally escape toward the top, bottom, and both sides of the refractory face 92, wherever that refractory face does not lie perfectly against the rim of tundish 22. The sideways escape of the flames, however, would rapidly result in weakening and deterioration of the tundish car arms 14, 16 and the adjustment mechanisms 40, 64. To prevent this from happening, perforated vertical pipes 106, 108 are provided along each side of the refractory face 92. The location of these pipes is best shown in FIGS. 5 and 6. The perforations in the pipes 106, 108 are so arranged that when the pipes 106, 108 are connected to compressed air supplies 110, 112, a curtain of compressed air is blown inwardly in a horizontal direction toward the center of the refractory face 92. This air curtain effectively prevents the lateral escape of flames from the burners 102, 104 and thus prevents damage to the tundish car arms 14, 16 and their associated mechanisms.

When the preheating cycle is completed and the casting apparatus of Patent No. 3,344,847 is ready for a clean tundish, the latch 66 is released, the preheating head 60 is swung back, the shield-and-preheater assembly 56 is swung out of the way about kingpost 58, the tundish 22 is returned to its upright position by operation of the air cylinder 28, the air supply to cylinder 28 is disconnected for safety reasons, and the tundish car 12 is moved around the turret to the position where it is needed.

It will be seen that the present apparatus provides a simple and eflicient cleaning and preheating mechanism which does not require the removal of the tundish from the turret, and therefore greatly decreases handling and speeds up operation. Obviously, the teachings of the invention can be carried out in a variety of ways of which the embodiment shown and described is merely illustrative.

I claim:

1. A tundish preheating station comprising:

(a) supporting means for supporting a tundish on at least one side thereof in preheating position;

(b) a burner assembly adapted to be positioned against the face of a tundish in preheating position to pre heat the same; and

(c) flame diversion means for diverting the flame of said burner assembly away from those sides of the tundish on which said supporting means are located.

2. The device of claim 1 in which said supporting means include means disposed on each lateral side of a tundish adjacent its face and arranged to turn said tundish on its side so that its face is vertical, and in which said burner assembly is disposed in a vertical plane.

3. The device of claim 2, in which said flame diversion means are disposed along the vertical edges of said burner assembly and are arranged to divert lateral flames toward the top and bottom edges of said assembly.

4. The device of claim 1, in which said flame diversion means includes perforated pipe means disposed along the edges of said burner assembly, and means for supplying compressed air to said pipe means; said perforations being oriented to direct an air stream toward the center of said burner assembly.

5. A tundish preheating and cleaning station comprising:

(a) a vertical heat shield having an opening formed therein for the passage of an oxygen lance therethrough; and

(b) a burner assembly having a radiant face disposed in a vertical plane;

(c) said heat shield and burner assembly being mounted for rotation about a common vertical axis and said burner assembly being so positioned that its radiant face faces away from an operator standing in a position to operate an oxygen lance through said heat shield.

6. The device of claim 5, in which said burner assembly is mounted for limited pivotal movement about a second vertical axis spaced from said common vertical axis.

7. The device of claim 6, in which said radiant face is mounted for limited pivotal movement about at least one horizontal axis spaced from said common vertical axis.

8. The device of claim 5, in which said burner assembly further includes, along its vertical. edges, flamediverting means arranged to blow air generally along said radiant face toward the center thereof.

9. A tundish preheating and cleaning station, comprising:

(a) support means for supporting a tundish in a fixed position with its face vertical;

(b) a heat shield having an opening formed therein for the passage of an oxygen lance, said heat shield in operating position being sufficiently spaced from said tundish face to allow maneuvering of said oxygen lance;

(c) a burner assembly having a vertically disposed radiant face, said radiant face in operating position being applied against the face of said tundish;

((1) said heat shield and burner assembly being mounted for rotation about a common vertical axis to selectively bring either of said heat shield and burner assembly into operating position. r

10. The device of claim 9, in which said burner assembly is mounted for individual movement about a second vertical axis spaced from said common vertical axis.

11. The device of claim 10, in which said radiant face is mounted for limited pivotal movement about at least one horizontal axis spaced from said common vertical axis.

12. The device of claim 9, further comprising a kingpost defining said common vertical axis, said kingpost being disposed on one side of said heat shield, and said burner assembly being mounted on said heat shield on the other side thereof and at generally a right angle thereto.

13. The device of claim 12, in which said burner assembly includes a mounting bracket fixedly mounted to said other side of said heat shield, for pivotal movement about said second vertical axis with respect thereto, and said radiant face and the burners of said burner assembly are mounted for limited pivotal movement about a horizontal axis with respect to said mounting bracket by means of an expandable member connected between said mounting bracket and said radiant face and burners.

14. The device of claim 13, in whichsaid radiant face and burners are mounted for limited pivotal movement about at least one horizontal axis with respect to said mounting bracket.

15. The device of claim 13, in which the fuel supply for said burners is conducted through said kingpost.

16. The structure of claim 15, further comprising flame diversion means mounted along each vertical edge of said radiant face and arranged to discharge an air .stream generally along said radiant faoe toward the center thereof.

17. In a continuous casting apparatus:

(a) a turret structure;

(b) tundish support means on said turret structure arranged to support a tundish for arcuate movement between a casting station and a preheating station;

(c) tilting means associated with said support means for tilting said tundish on said support means from its face-up casting position to a preheating position in which its face is vertical and faces radially outwardly from said turret;

(d) a burner assembly having a vertically disposed radiant face; and

(e) means for moving said radiant face against the face of said tundish in its preheating position on said turret to preheat the same in situ.

18. The structure of claim 17, in which said burner assembly is mounted for limited multidirectional pivotal movement so as to cause said radiant face to lie against said tundish face regardless of warpage.

19. In a continuous casting apparatus:

(a) a turret structure;

(b) tundish support means on said turret structure arranged to support a tundish for arcuate movement between a casting station and a cleaning and preheating station;

(c) tilting means associated with said support means for tilting said tundish on said support means from its face-up casting position to a cleaning position in which its face is vertical and faces radially outwardly from said turret;

(d) a heat shield at said cleaning and preheating station, said heat shield having an opening formed therein for the passage of an oxygen lance, said heat shield in operating position being sufiiciently spaced from said tundish face in its cleaning position to allow maneuvering of said oxygen lance;

(e) a burner assembly having a vertically disposed radiant face, burners mounted to discharge flames through said radiant face, and a vertically disposed shielding face, said radiant face in operating position being applied against the face of said tundish;

(f) said heat shield and burner assembly being mounted for rotation about a common vertical axis spaced from said turret to selectively bring either of said heat shield and burner assembly into operating position.

20. The structure of claim 19, in which said radiant face is mounted for limited pivotal movement about a second vertical and a horizontal axis each spaced from said common vertical axis.

21. The structure of claim 20, in which said radiant face is mounted for further movement about a second horizontal axis parallel to said first-mentioned horizontal axis.

22. The structure of claim 21, in which said heat shield is supported on one side on a kingpost defining said common vertical axis, and said burner assembly is mounted to the other side of said heat shield by a pivot post defining said second vertical axis.

23. The structure of claim 21, further comprising flame diversion means mounted along each vertical edge of said radiant face and arranged to discharge an air stream generally along said radiant face toward the center thereof.

24. The structure of claim 21, further comprising a slag box positioned adjacent said turret, said tundish face in its cleaning position and said radiant face in its operating position being above said slag box, so that said slag box need not be removed for preheating but may be vertically lifted when said tundish is out of its cleaning position and said burner assembly is out of its operating position.

References Cited UNITED STATES PATENTS 826,147 7/1906 Croxton 2635 JOHN J. CAMBY, Primary Examiner US. Cl. X.R. 263-50 

